long story short.
when u cold start the car and rev it, rpm work normal, car functions how it should.
when car is warm and u rev, the rpms lag and u hear the intake struggling to pull in air.
at around 4k rpms you also hear the timing chain ping sound.
Maf was changed and still the same issue.
car has NO ENGINE LIGHT

what could possibly be holding the car back.
6 speed btw

 

Milage ?
When precats are clogged , they can definitely restrict the engine performance ...
Check your precats and the main cat......

 

Milage is 101330 and tested the temp. On the 2 cats on the exhaust manifold 430degrees.

 

Air filter okay? Is there a rattle at 2k at all?

 

No rattle, air filter good. This def has me stumpped..

 

how many usernames you have ? are you the same as the OP ?

 

i got the same prob...

 

Actually pundo is my friend who recommended me to sign up on maxima.org. he came checked out my car, test drove it cause who ever I was telling about this syptom looked at me like yea sure and theydidnt know where to turn. First was mass air, replaced , air filter cleaned, checked coils, hoses. Then today I checked the cats coming from the head and I saw with a infered light 436 degrees. I did a search on maxima.org for the temps, but found nothing. All help is appreciated. I was also told about a fail safe mode. But I don't know how to do it. If I don't get it right by the end of this week its going to dealer.

 

coolant sensor...... or Iacv

 

i gutted my cats today, nothing... all sensors check out. maybe a bad ecu

 

Sounds like maybe an intake manifold gasket leak

 

i had the same problem and fixed it today.. bad ecu.. i got a junkyard one with the same numbers and had the dealer reprogram it for my key and such because it wont start without doing it. cars runs perfect

thats after
new maf
new knock sensor
gutted cats

 

Well last time this type of thing happened to me it was the knock sensor, namely the plug. Damned thing came apart and was grounding out on the motor.

 

Yep, most likely KS issue.

 

Not ks.

 

Hey everyone, that's for the help. But after $ 320.00 plus $230. Forund the problem it was the cat on the bottom of the car clogged. Went to shea stadium $40.00 to cut the cat off and put pipe. Car runs awesome. Again fellas very much appreicated. Thank you. You guys know how to diagnose the cars and be honest someone did say gut the cat. But when you are looking at money spending its hard.